A reference chromosomal map of the hot chili pepper Capsicum pubescens cv. “locoto” (Solanaceae)

AGUILERA, PATRICIA MABEL; DEBAT, HUMBERTO JULIO; SEIJO, JOSÉ GUILLERMO; GRABIELE, MAURO

RODRIGUESIA

Jardín Botánico Río de Janeiro

Año: 2021 vol. 72

0370-6583

Capsicum pubescens is a cultivated hot chili pepper, consumed in Latin American cuisine as a distinctiveingredient, and popularly known as ?locoto? or ?rocoto?. This taxon is also an outstanding source ofresistance to biotic and abiotic stresses as well as other valuable fruit traits for breeding of the worldwidelycultivated C. annuum and related species. In this study, the chromosome complement of C. pubescens cv.?locoto? (2n = 24) was deeply characterized through a sequential combination of conventional and molecularcytogenetics approaches comprising: Ag-NOR staining, heterochromatic fluorescent C-DAPI, DAPI/AMDCMA/DA bandings, fluorescence in situ hybridization (FISH) of Capsicum-derived probes of the 5S and18S-25S rRNA genes and different regions of spacers of the ribosomal unit, as well as telomeric probe. Themarkers identified were systematically combined with morphological karyotype parameters - number, size,centromeres, satellites - to produce a physical map which allowed the identification of several landmarks ineach individual chromosome. The reference chromosomal map of C. pubescens here presented is the mostcomprehensively developed in Capsicum so far. It is envisioned that this chromosomal map will serve asa reference framework for the upcoming sequencing projects and as starting point to assist future geneticmapping of important agronomic traits.